Hello,

My 1995 Explorer's Heater does not blow out of vents occasionally. Only out of front defroster?


blows out of front defroster?

 

You have a vacuum leak. Car engineers design the system to "default" to defrost with the absence of vacuum supplying the heating and a/c controls and blend doors. A likely place to look is under the hood at the vacuum resevour or the line attached to it. It will either resemble a large tin can, plastic ball or a plastic cannister mounted on the fender well in the engine compartment.It is common for these resevours to leak or vacuum lines leaking.

 

That is great advise- thank you.